f = open("file", "r")
str = f.read()
f.close()
lst = []
for paquet in str.split("\n\n"):
    Sum = 0;
    for sub_paquet in paquet.split("\n"):
        if (sub_paquet != ""):
            Sum += int(sub_paquet)
    lst.append(Sum);
lst.sort();
print(sum(lst[-3:]))